Computer peripheral devices such as CD-ROM, CD-R, HDD (hard disk device) and other disk devices have an electrically erasable and programmable read-only memory (EEPROM) in which a program known as firmware for controlling the disk devices is stored. Version updating or bug correction of firmware in the disk devices is executed by updating the firmware in the EEPROM.
In the case these disk devices are general-purpose devices, generally, the computer updates the firmware as follows.                An update firmware is taken into the HDD of the computer through floppy disk or the Internet.        A disk device is designated, and the update firmware is transmitted.        The disk device receives the update firmware, and writes it into the EEPROM.        
However, if there are plural disk devices of a same type, the disk device to be updated must be correctly designated.
If the firmware of a wrong disk device is updated, this disk device may fail to function normally.
On the other hand, in the case of a system composed of non-general disk devices, for example, in the case of jukebox or auto-changer, it is not easy to supply a new firmware from outside.
For this purpose, the update firmware is supplied into the disk device by using a special tool, or the disk device is dismounted from the system, and connected to a different computer, and the firmware is updated in each device.
As a result, the firmware updating is a complicated job, and in the case of a plurality of disk devices, each device must be dismounted and updated in order to update the same firmware.